Book 1, Question 146
Why Does Baking Soda Fizz? A Base Meets an Acid!
Fizz! Baking soda is a base and vinegar is an acid, and when they meet they make carbon dioxide bubbles, shown as CO2 on the page. The page says the fizz is a gas you already breathe out. Try it with a grown-up by mixing a pinch of each in a cup.
From the book
Page from A Million Whys Book 1
More fun facts
- Acids release tiny positively charged particles called hydrogen ions. Bases grab them.
- We taste acids as sour and bases as bitter.
- Scientists measure acids and bases with the pH scale. Pure water sits in the middle and is neutral.
- Bases all come in above 7 on the pH scale.
- White vinegar has a pH of about 2.4.
- Vinegar also fizzes on limestone, because it reacts with a material in the rock called calcium carbonate and releases carbon dioxide.
- NASA's JPL suggests making a model volcano with baking soda, vinegar and play dough.
Sources: Science News Explores, Science News Explores, National Geographic Kids, NASA
Questions kids ask
What is the pH of vinegar?
White vinegar has a pH of about 2.4, which makes it an acid.
Why does vinegar make some rocks fizz?
It reacts with calcium carbonate in rocks like limestone and releases carbon dioxide gas.